Disable Smilies in This Post. Show Signature: include your profile signature. Only registered users may have signatures.

*If HTML and/or UBB Code are enabled, this means you can use HTML and/or UBB Code in your message.

If you have previously registered, but forgotten your password, click here.

T O P I C R E V I E W

Tykeanaut

Spaceflight Now reports that statistics show the International Space Station came under growing danger from space junk after 2007...

...with half of the orbiting lab's close calls since then due to near-collisions with debris from a Chinese anti-satellite missile test, the mysterious explosion of a Russian military spacecraft, and the cataclysmic high-speed crash of two satellites.

Is there any possibility or benefit from boosting the ISS into a higher permanent orbit?

Jim Behling

quote:Originally posted by Tykeanaut:Is there any possibility or benefit from boosting the ISS into a higher permanent orbit?

No, then Soyuz and Progress would be unable to reach it.

SpaceAholic

To significantly reduce the threat, ISS would have to be boosted above 1200 nautical miles (lots of energy required to raise the station and get to it); it would also alter the orbital period to over two hours - whatever tangential effects that would have on power, thermal cycling, ground control, etc. would also have to be considered.

issman1

What I find a bit confusing is that the engines of the Russian Zvezda module may not last till 2020 if used too often, yet they have been used in several instances for orbital debris avoidance.

It has also been confirmed that after the fifth and final Automated Transfer Vehicle undocks in 2014, the ISS will no longer need boosting. Moving the station higher in low earth orbit thereafter was not only ruled out but is impractical.

Robert Pearlman

quote:Originally posted by issman1:...the ISS will no longer need boosting.

I don't believe that is correct.

The linked article reports that due to the ATV, the station's propellant tanks have or will be filled to capacity, and commercial U.S. flights will have the ability to refill them as needed.

SpaceAholic

Propellant is only one limiting factor - the Zvezda reboost engines have a rated service life of just under 7 hours each.

Robert Pearlman

But that still doesn't negate the need or ability to do re-boosts. The engine on the Progress cannot only serve this role, per NASA, it provides the primary method for reboosting the ISS.

kyra

The good news is that it doesnt take radical orbit changes when a potential collision is seen possible many orbits in advance. The tracking and prediction abilities get better all the time.

issman1

ISS is now at its highest altitude yet, 270 miles. Are there plans to boost it even higher before the final ATV departs in 2014, perhaps in excess of 300 miles?

Jay Chladek

Over 300 miles? Only if a Soyuz or a Progress can reach that altitude (which I am not entirely too certain if they can).

issman1

It's all about longevity. The higher the station is the lower the risk of it ending up like Skylab. That said, the Hubble Telescope is predicted to re-enter by the end of this decade. A sad fate unless it can be reboosted by someone with the means to.

Incredulous also to think Progress, Soyuz, HTV or even Dragon can only reach the lowest point in a low earth orbit.

Jim Behling

quote:Originally posted by issman1:Incredulous also to think Progress, Soyuz, HTV or even Dragon can only reach the lowest point in a low earth orbit.

Why is it incredulous? The higher the ISS, the less the spacecraft can carry.

A small piece of space junk or naturally occurring celestial debris created the tiny hole in one of the space station's wing-like solar arrays at some point in the outpost's 14-year history in orbit. Canadian Space Agency astronaut Chris Hadfield spotted the puncture and posted a photo of it on Twitter on Monday (April 29).